ON CRUSTACEA BROLKiHT BY DR WILLEY FROM THE SOUTH SEAS. 633 



quarter of an inch, is not put out of court by any great superiority of size. Unluckily 

 Dana has only given a rather meagre description of it and no complete figure. But he 

 states that the first pleon segment is nearly concealed under the peraeon, that the uropods 

 do not reach beyond the telson, and that their setae are not half as long as the rami. In 

 the.se respects, therefore, it differs from our species. His account of the legs is obscured 

 by what must be a misprint. He says of them that ' the fourth joint of the third 

 pair is a little shorter than either the third or fifth pairs, and longer than the tarsus.' 

 If the word 'pairs' has slipped in by mistake where 'joint' was intended, the passage 

 would mean, according to our enumeration of limbs and joints, that in the first 

 peraeopods the fifth joint is shorter than the fourth or the sixth, which would be a 

 character common to several species, but it would further mean that the fifth joint 

 is longer than the seventh. This interpretation will agree with Dana's figure of the 

 limb, but that figure shows the fourth joint only a little way produced over the outer 

 margin of the fifth, instead of to its extremit}' as in our species. 



ClROL.iNA ORIENTALIS, Daua. 



1853. Cirolana orientalis, Dana, U. S. Expl. Exp., vol. 13, pt. 2, p. 773, pi. ol, 

 fig. 7 a — d. 



1890. Cirolana orientalis, Hansen, Cirolanidae, p. 117, pi. 4, fig. 1 — ih, in 

 K. D. Vid. Selsk. Skr., Ser. 6, vol. 3, p. 353. 



As pointed out by Hansen, there are two striking features in this species. 

 " The head is produced in front into a large, advanced process, apically dilated, 

 coalesced with the frontal plate, and truncate in front," and the uropods are peculiar, 

 the inner ramus being emarginate on its outer edge, and the outer ramus, which is 

 the longer, having its outer edge bai'e. Dana's figures show the cephalic process but 

 ignore the emargination of the uropod, which was perhaps regarded as an accidental 

 malformation of the ramus. The terminal segment has a pair of well-marked pits 

 or depressions near the base. 



Hansen describing a subadult female, gives fifteen joints for the flagellum of the 

 first, and twenty-one for that of the second antennae. His specimen was 10\S mm. 

 long. In a specimen 12 mm. long, I find the flagellum of the first antennae having 

 on one side seventeen, on the other only twelve joints, in each case the joint next the 

 peduncle being extremely short. Corresponding to these two respectively, the flagella 

 of the second antennae had twenty-four and twenty-five joints. 



The cutting edge of the right mandible is formed of three large approximate 

 teeth, the uppermost rounded, the other two triangular. In the left mandible between 

 the rounded upper and the triangular lower tooth there is a broad low tooth giving 

 a very different appearance to the cutting edge of this organ. 



In the maxillipeds the second joint is much the longest, apart from its produced 

 plate, which is also long, armed with several plumose setae and near its rounded 

 apex with a single strong hook ; the fifth joint is much larger than the sixth. 



The specimens were labelled as surf isopods, Conflict Group, New Guinea. A single 

 specimen was from ' Isle of Pines.' 



